mx5cartalk.com

Hi guys, the following little problems are annoying me a bit... I have an '89, and it's JDM if that makes any difference

1. Oil pressure dropping to zero on heavy braking for about a second or two. Oil is due for a change shortly (hoping to get it done this weekend, along with the box and diff oil, the diff looks fairly simply but im not 100% sure where the fill/empty spots are on the gear box)

2. Car revs dipping and going up and down a little at lights (though I've done a bit of reading and apparently this is very common for NA's) I have a 13B AFM on there if that makes any difference, car did the same thing even with the stock one though - and that leads me to another point.... Is there a way to tune the A/F ratio on the AFM without actually being on a dyno with an A/F reader

3. There's some body filler thats finally bubbling up the paint a little on my drivers side door.... it's starting to crack and soon enough it will probably just fall off and I'll have to get the door re-filled/or get a new black door. Is there a way I can put a wax or sealant or SOMETHING over the bubble to keep it \"down\" ? I will take a photo later to show you guys what I mean. I know this is dodgy but it would totally suck if that bubble got ripped off somehow.

4. Several rattles but I'm not game to even BEGIN to try and fix them

Oh, just remember #5:

When my headlights are on (i.e. up and on) , my high beams actually flash on and off when I go over bumps sometimes, or finish going around corners (i.e. cancelling the indicator..)

Must be something in the indicator stalk... actually, if it was high beams then in would be the on/off switch in the steering column, correct?

1. check your oil level immediately! conversely it could be a sender or gauge problem.

2. The AFM will be contributing no doubt. You can tweak idle speed with the throttle body bypass screw, but check your mixtures. Buy a Jaycar AFM kit and plug that into your O2 sensor, and observe your mixtures on the road. Adjust the AFM flapper tension as necessary (though it's a difficult balancing act).

#5: What happens when you kick/bump the steering column with the lights on? If the lights are fine it's probably not an indicator stalk problem. In that case continue kicking various bits in your car till you narrow it down.

jonno.

Matty wrote:1. check your oil level immediately! conversely it could be a sender or gauge problem.

2. The AFM will be contributing no doubt. You can tweak idle speed with the throttle body bypass screw, but check your mixtures. Buy a Jaycar AFM kit and plug that into your O2 sensor, and observe your mixtures on the road. Adjust the AFM flapper tension as necessary (though it's a difficult balancing act).

Thanks matty.. Oil level is about 3/4, but I am doing a change this weekend anyways... Obviously a 0psi oil pressure reading is bad.. i.e. no oil... but it only happens for a second or two when I brake really hard

Simple solution - don't use the brakes at 3/4 full you are probably getting enough oil surge to starve the pickup under really heavy braking - this is BAD! Whenever oil pressure drops ALWAYS check the oil level and top up if necessary. Bearings starved of oil even for very short periods can sieze/grab.

I have heard of dipsticks loosening from the knob, and therefore reading more oil than is actually in the engine. Rare, but possible...

bigdog wrote:Simple solution - don't use the brakes at 3/4 full you are probably getting enough oil surge to starve the pickup under really heavy braking - this is BAD! Whenever oil pressure drops ALWAYS check the oil level and top up if necessary. Bearings starved of oil even for very short periods can sieze/grab.

Damn, your right... I DID check the oil, and yeah it was still around 3/4 or so (cold of course)..... Added another litre and now its fine Cant seem to make it go any further down than 0.75 under REALLY heavy breaking ... i.e. locking it up on my street doing 40 km/h, with my neighbours wondering wtf im doing

Would I have done any damage? I kind of dismissed the oil level as being the culprit originally... because I thought around 3/4 full was around optimal for most cars?

Proven wrong I spose! (Once again )

Doubt you've done any damage unless you can hear the engine rattling or knocking (I hope that's not what you meant by gripe number four!). You might 've flat spotted a tyre trying it out though...

bigdog wrote:Doubt you've done any damage unless you can hear the engine rattling or knocking (I hope that's not what you meant by gripe number four!). You might 've flat spotted a tyre trying it out though...

Well, the lifters have always been noisy, and the ticking isnt any louder, so i dont tihnk ive spun any bearing in the bottom end, or anything like that

*phew*

Nah tyres are OK, i just exaggerated it alot to make the post and myself appear more interesting LOL

i was gunna say.........if you can lock it up at 40 k's, you need to get the brakes looked at.....................LOL

I always thought the difference between high and low on the dipstick was between 0.8 and 1 litre. So if it said 3/4 on the dipstick and you added a litre doesn't that mean it's over full now?

Garry wrote:I always thought the difference between high and low on the dipstick was between 0.8 and 1 litre. So if it said 3/4 on the dipstick and you added a litre doesn't that mean it's over full now?

Oh poo

that would explain the excess amount of smoke coming out the exhaust when I started the car this morning

I'm doing an oil change tomorrow anyways

Number #5:
I get this issue aswel, but when the car has been parked with the soft top and in the sun for a bit. Sometimes the highbeams are on when indicator stalk is in 'neutral'.....i fix the problem (when the lights are off) by pushing the stick into highbeam 'on' (ie away from u)

solution to your head light problem

push the stalk forward before you get out of the car ;)
I have done it religiously for 5 years!

only solution is a new stalk assembly
its a pain in the a**!

aqnd just live with the occasional light flashing @ night!!